Results 251 to 260 of about 175,835 (309)

Reducing Supply Current Harmonics

IEEE Industry Applications Magazine, 1998
In this article, a simple and effective method for reducing the supply current harmonics has been proposed for a parallel connected 12-pulse thyristor converter with an interphase reactor. The proposed method requires only an interphase reactor with an optimal inductance value being much smaller than conventional inductance values, without any ...
Toshihiko Tanaka, Naotsugu Koshio, Hirofumi Akagi, Akira Nabae   +3 more
openaire   +1 more source

Comparison of versatile harmonics current compensation and specific number harmonics current compensation

Proceedings of the IEEE International Conference on Industrial Technology (ICIT'96), 2002
New compensation method of specific number harmonics currents is proposed and its excellent compensation effects are explained in comparison with conventional versatile compensation. In addition, preference compensation of specific number harmonics currents is also proposed and experimental data with a small model proves the superiority of this method.
M. Yano, S. Kuramochi, N. Nanaumi
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Non-harmonic alternating currents

Journal of the A.I.E.E., 1927
Certain principles are presented for solving non-harmonic a-c. problems. Graphical methods are already well known for solving practically any problem, when currents and electromotive forces are sinusoidal, by vector diagrams in a plane. In certain special cases such diagrams give correct results when currents and electromotive forces are non-sinusoidal,
openaire   +2 more sources

Harmonic pricing model based on harmonic costs and harmonic current excessive penalty

2011 2nd International Conference on Artificial Intelligence, Management Science and Electronic Commerce (AIMSEC), 2011
Harmonic will do great harm to power grid and cause economic losses. In order to reduce such losses, the power utilities need additional investment for harmonic suppression measures. The harmonic losses and the additional investment capital together constitute the harmonic costs and they are the basis of harmonic pricing.
null Yong Peng, null Shun Tao, null Qun Xu, null Xiangning Xiao   +3 more
openaire   +1 more source

Harmonics in transformer magnetizing currents

Proceedings of the American Institute of Electrical Engineers, 1915
The purpose of this paper is to show in a concise manner the cause and effects of higher harmonic currents in magnetizing currents of transformers. A hypothetical case is analyzed to show the cause of the harmonics; then the schemes of connecting transformers that are commonly used for polyphase transformation are taken up and the effects of the ...
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Harmonics in opposed current converters

IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society, 2012
Practical switching devices have finite turn-on and turn-off times. Normally a blanking time is added between the turn-off and turn-on of switches to avoid a short circuit during switching. This blanking time results in a current dependent voltage error of the pulse width modulated output of a converter.
Schellekens, J.M., Duarte, J.L., Huisman, H., Hendrix, M.A.M.   +3 more
openaire   +2 more sources

Harmonic Contributions Evaluation With the Harmonic Current Vector Method

IEEE Transactions on Power Delivery, 2008
A method to evaluate harmonic contributions at the point of common coupling is presented in this paper. The proposed approach is based on the harmonic current vector method where reference impedances are introduced. Resistance defined at fundamental frequency with measurements is used as the customer-side reference impedance.
Tomaz Pfajfar, Bostjan Blazic, Igor Papic   +2 more
openaire   +1 more source

Harmonic measurements: current and voltage transducers

199 IEEE Power Engineering Society Summer Meeting. Conference Proceedings (Cat. No.99CH36364), 2003
An overview of the development of special current and voltage transducers at the National Research Council of Canada for accurate measurements of harmonics in power systems will be presented. The transducers include two-stage and electronically-aided instrument transformers, openable-core AC and AC/DC current transformers, multi-stage clamp-on current ...
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Inductive load current harmonic injection

Proceedings of the Thirty-Fourth Southeastern Symposium on System Theory (Cat. No.02EX540), 2003
Induction motor audible noise can be related to the frequency content present in the stator winding currents. These currents produce time varying air gap fluxes which in turn produce exciting forces resulting in vibrations in the mechanical structure. By adding harmonics into the winding currents, additional frequencies can be added to the air gap flux
B. Brzezinski, J. Parker, T.A. Haskew, J. Murphree, D.J. Jackson   +4 more
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Current Harmonics Measurement by Means of Current Transformers

IEEE Transactions on Power Delivery, 2007
This paper analyzes the accuracy of current transformers (CT) when excited with nonsinusoidal currents. It uses a nonlinear model that accounts for the minor hysteresis loop of the core. It was concluded that instrument transformers with accuracy class 0.6 or better provide reasonably accurate measurements of current harmonics magnitudes, however the ...
Alexander E. Emanuel, John A. Orr
openaire   +1 more source